Well, ideally it should work like this:
1 BTC is lent by Alice to John
John re-lends it to Joe
Joe pays back john 1 BTC, who then settles his debt with Alice with that same 1 BTC.
But, this model is broken too, since this example hinges on the lenders and debtors owing the entire supply of the currency, which simply does not occur IRL.
Its nor broken. Its the failure of the gold standard. Doesn't matter the amount of BTC in existence, It can grow infinitely in DEBTS it has to pay. I could loan 1 BTC to 10 BTC of debt
So, what you are saying is we need to eliminate debt?
Bitcoin with tokens is the solution. So business can color tokens redeemable in goods or services only. They become self issuers of credit.
Isn't untokenized Bitcoin already redeemable in goods or services only? Or are you talking about making a gift-card esque economy where spending is restricted to specific applications?
http://www.moneyasdebt.net/ - Self issued credit is explained better here. Bitcoin as a single uniform commodity money will fall into perpetual debt, just as gold did.
